I love my Chevy Chevette!
Posted: 07/06/13 10:58 PM
Hi guys. This is my first post and I want to say hi to everybody and thanks in advance. I'm a novice engine builder but am smart enough to do lots of homework and ask for help from more knowledgeable people than me. I'm looking for some advice on building a pump gas Hydraulic roller 327. I have researched a lot of the 60's era builds but they were all 11:1 compression motors with solid cams (30 30 cams). I'm looking to get about 425 HP and even more important as much torque and mid range power that I can get out of this mighty mouse on pump gas (9.5:1 compression). This will be a 80% street vehicle (and yes before anyone says it, I know that I could get more power out of a 350 or 383 but everybody have those and i want something different. I have built a 350 but have always been interested in the mighty mouse 327's ...plus a 327, would be more correct to the truck it's going in) Here's what I have. I have a 1966 Chevy short-wide PU. It has a 12 bolt with 3.73 gears with a 700R4. I'm going to have about a 2000-2500 stall. I have a 68 327 block with forged crank that unfortunately will have to go to .060 over to be cleaned up. The block is at the machine shop as we talk getting bored, aligned honed, decked to .010, and balanced. I thought about going with a 6" rod but have decided to stay with 5.7's. To get my compression ratio right (about 9.5:1), I'll be using forged flat top pistons (probably Speed Pro brand) with Moly rings, machine shop owner is going to recondition some forged i beam connecting rods (he builds a lot of circle track cars and some customers replace them after one use but he guarantees that they are good). I will be using ARP rod and main bolts. Machine shop owner recommended following cam XE294 HR from Comp cams. it's duration at .050 is 242 (intake) and 248 (exhaust) with 110 degree lobe separation and valve lift of .54 (intake) and .562 (exhaust). Is it too radical? I have always used hydraulic flat tappet cams but was told that a roller could take more duration. This will mainly be a street truck (no AC but possibly could have some day) so I don't want to accidentally put to much cam in it like a lot of people do. Does this cam look OK to you guys? As far as the heads, I'm looking at the Dart SHP, Aluminum, Assembled, 72cc Chamber, 200cc Intake Runner Cylinder Heads. They have 2.02 intake and 1.6 exhaust valves. (I don't know if I should go with a smaller intake runner size 185 cc or larger ones like the 200 cc or 215 cc. Can someone explain this too me? These heads are assembled but I will match springs to cam. I plan on using an Edelbrock Performer RPM Air Gap intake (1500 to 6500 rpm). I have two carburetors to choose from. I have a Holley 4150 750 Double Pumper or a 600 cfm Edelbrock. I'm thinking the Holley 750 might be best. Anyways, guys any and all advice would be appreciated. Thanks